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modulation, in communications

(Encyclopedia)CE5 Modulation modulation, in communications, process in which some characteristic of a wave (the carrier wave) is made to vary in accordance with an information-bearing signal wave (the modulatin...

horology

(Encyclopedia)horology hōrŏlˈəjē [key], science of measuring time and technology of constructing instruments for its measurement or recording. Early measurements of the passage of time were based on observatio...

communication

(Encyclopedia)communication, transfer of information, such as thoughts and messages, as contrasted with transportation, the transfer of goods and persons (see information theory). The basic forms of communication a...

data communications

(Encyclopedia)data communications, application of telecommunications technology to the problem of transmitting data, especially to, from, or between computers. In popular usage, it is said that data communications ...

Energy, United States Department of

(Encyclopedia)Energy, United States Department of, executive department of the federal government responsible for coordinating national activities relating to the production, regulation, marketing, and conservation...

smart card

(Encyclopedia)smart card, small device that resembles a credit card but contains an embedded microprocessor to store and process information. Magnetic-stripe cards, which store a very small amount of information (m...

migration of animals

(Encyclopedia)migration of animals, movements of animals in large numbers from one place to another. In modern usage the term is usually restricted to regular, periodic movements of populations away from and back t...

Jansky, Karl Guthe

(Encyclopedia)Jansky, Karl Guthe, 1905–50, American radio engineer; b. Norman, Okla. After graduating (1927) from the Univ. of Wisconson, he joined the Bell Telephone Laboratories. While trying to determine the c...

air, law of the

(Encyclopedia)air, law of the, in the broadest sense, all law connected with the use of the air, including radio and satellite transmissions; more commonly, it refers to laws concerning civil aviation. The developm...

Ryle, Sir Martin

(Encyclopedia)Ryle, Sir Martin, 1918–84, British radio astronomer, B.S. Oxford, 1939. Ryle was a researcher and professor at Cambridge from 1945 until his retirement in 1982. Knighted in 1966, he was Britain's As...